Before it was a screw in thing, there were like little metal pin tabs that the batts would rest against to get their charge. I didn't have a problem with mine, but a lot of people had connectivity issues.
You know, I haven't counted, but I could start. I usually keep one charging in the pcc while another charges in the wall and my trifecta plugged in so I don't pay a lot of attention to it. I don't think I could be trusted to keep count out of the house, but adding a slash to a post it note in the house could be doable.